Hugo Chávez's ambition to lead Venezuela for decades to come hung in the balance last night as the country voted in a constitutional referendum that could abolish presidential term limits, paving the way for his indefinite re-election.

Opinion polls gave him a slight edge after a controversial campaign that pitted student protesters against police and turned the state into a "red machine" to deliver a yes vote.

The president said he wanted to run again when his term ends in 2013, with unlimited re-election rights, to protect his self-styled socialist revolution "from enemies at home and abroad". The vote, he said in a newspaper column, would either safeguard or sabotage a historic process of transformation and liberation that had lit up South America. "It is the dilemma of Shakespeare's Hamlet: to be or not to be," he said.

The 54-year-old former tank commander has spoken of ruling in Venezuela beyond 2030.

Yesterday military-style bugles sounding from government vehicles roused people from dawn and queues swiftly formed outside polling stations. Activists in red T-shirts handed flyers with 10 reasons to vote yes. Number one: "Chávez loves us and love is repaid with love." Number two: "Chávez is incapable of doing us harm."

Some families were split over whether to support a charismatic leader popular for spending oil revenues on social programmes but resented for economic problems and concentrating power in his hands.

"I am going to support my president. Thanks to him I have free healthcare," said Marisabel Torres, 56, a housewife in Caracas. Her husband Ricardo, 56, a courier, was voting no. "Chávez has screwed this country enough already."

In December 2007 Venezuelans narrowly rejected a similar referendum covering presidential re-election - which would have removed the limit on the number of times a president could stand for office - prompting an opposition slogan for the latest campaign: "No means no." This time the president widened the scope, to abolish term limits for mayors and governors.

The opposition say that the Chávez-appointed electoral authority has ignored abuse of state resources.

But, despite collapsing oil revenues, which have blown a hole in the government budget, and warnings of stagflation, the president said a yes vote would bring a bounty. "Today is the beginning of the time of big harvests," he said.